On Friday afternoon, the Sheffield United footballer Ched Evans was sentenced to five years in jail for raping a 19-year-old woman. His co-accused, Port Vale footballer Clayton McDonald, was found not guilty.

Almost immediately, the #ChedEvans hashtag appeared on Twitter, and later, #JusticeForChed. Some tweets questioned why one defendant was found guilty and the other not. Others blamed the victim, particularly focusing on her being drunk; some could only be described as vile. Tweeters included fellow Sheffield United footballer Connor Brown who has since deleted his attack on the victim, which included calling her a slag, and which intimated she made her complaint for financial reasons.

Rape culture, which includes victim blaming, sexual objectification and trivialising rape, was demonstrably alive and well on both hashtags, and continued all weekend.

By early Sunday, the name of the woman who was apparently the complainant was being widely tweeted, it first having been seen on Friday. The insults became more personal, and the levels of abuse directed at the victim increased throughout the day.

Although the Twitter community had, since the hashtags started, attempted to correct the views of supporters of Ched Evans by reminding them that a jury had heard the full facts; that victim blaming was never right; that alcohol consumption can and does render a person incapable of consent, the community rounded even more so once the tweets started including the alleged name of the victim.

People were quick to point out to those using the name that their behaviour was unlawful, warning that screenshots were being taken, and the police were being contacted. Some users took to Storify and Tumblr to capture the tweets in an attempt to assist the police, leading to a North Wales police spokesperson saying on Sunday afternoon that they were collating all the relevant information.

Rape survivors fall into a special category of victims of crime, entitled to lifelong anonymity. No details or images of the survivor are to be published if the publication could lead to the identification of the person.

Holly Dustin, the director of End Violence Against Women, issued a statement saying: "It has long been law that rape complainants are protected by lifetime anonymity and those who have named her have been reported to the police for committing a criminal offence. This raises serious questions about the adequacy of the criminal justice system to deal with offences that occur online and we are calling for an urgent review of laws and practices."

Does it raise questions about the adequacy of the criminal justice system?

Broadly speaking, law isn't a shield to prevent a bad thing happening – it cannot stop people behaving in a certain way; it can only prescribe a punishment or remedy should people behave in a certain way. Our modern digital world enables us to see more easily behaviour we knew existed. The criminal law exists because we recognise the potential for people to commit the behaviour.

Under the Sexual Offences (Amendment) Act 1992, a breach of the anonymity afforded to rape survivors occurs if a person causes identifying matter to be published in England and Wales in a written publication available to the public. Until this is tested, we do not know if the courts will determine that Twitter falls into a "written publication available to the public", and indeed whether the "publishing" occurred in England and Wales. However, there are other legal avenues available to punish tweeters, such as section 127 of the Communications Act 2003, if the tweets can be deemed to be grossly offensive or of an indecent, obscene or menacing character; and section 4A of the Public Order Act 1986 if the tweets can be deemed to contain threatening, abusive or insulting words. Both have previously been used in successful prosecutions of tweeters, and can carry more significant sentences than the anonymity provision, which is limited to a fine.

While it may be without doubt that those who used Twitter in an unlawful way over this issue should be punished, and it is fair to say that the law is constantly being tested in its application in our new media age, what this weekend has demonstrated is how alarmingly alive and pervasive rape culture is. Isn't the biggest question what we do about that?